Yep that's usually how it happens. I have 3 cds that have hidden tracks.
Aerosmith's Just Push Play has one at the end of the cd after "Avant Garden". On Lionel Richie's double greatest hits album, on disc two, it lists only 4 tracks...but there are actually 5. The 5th track being the Commodores hit "Brickhouse"
And on Weird Al's "Off The Deep End" album, after "You Don't Love Me No More" there's some goofy sh!t by Al and company.
I remember in 2001 how there was some people claiming there was a hidden track on Invincible, but no one could get their story right. 1 person said it was tucked between Break Of Dawn and Heaven Can Wait, another said it was after "Threatened"